1. Field of the Invention
The present invention relates to motor vehicle heaters and in particular, the present invention relates to motor vehicle heaters that warm the interior of the motor vehicle prior to starting of the car.
2. Description of the Prior Art
In cold weather, the starting of a motor vehicle is an extremely uncomfortable task. Further, when the motor vehicle owner does not own a garage, the windshield of the vehicle commonly has frost or snow from the night before. The frost or snow presents an additional undesirable task that includes cleaning the windshield every morning in the cold. If the windshield is not cleaned properly, the frost or snow present a hazard or danger in driving the vehicle. One solution to the cold and frost and snow is to start the motor vehicle and allow it to run in place, warming the interior and defrosting the windshield from frost or snow. This method, however, is wasteful in that it uses a precious fossil fuel, the price of which keeps escalating. Moreover, this method requires normally getting out to start the car well prior to when it is desired to drive the vehicle.
In the prior art, several patents attempt to provide another solution by prewarming the interior of the motor vehicle without the use of power from the engine. The Allman U.S. Pat. No. 2,819,373 shows an electric heater with a blower mounted in the front portion of the vehicle beneath the dash. Electrical energy is supplied by a detachable cord which is connected to a house current. The electrical power is switched on and off in the house by a switch connected to the cord. The solution of the Allman patent, however, poses a problem for installation in existing cars because of the congestion caused by other devices being beneath the dash and the difficulty of installation through a firewall. Further, one must wait for the interior of the car to be warmed before the windows start to defrost since the air is not directed near any of the windows.
The Hercher U.S. Pat. No. 3,221,138 shows a pre-startup car heater that uses house current and is mounted on top of the dash in the interior of the motor vehicle. The Hercher patent solves the installation difficulty due to the congestion beneath the dash but poses a new problem of having a heater mounted on top of the dash, decreasing the amount of viewing area for the driver and presenting a possible safety hazard if a collision occurs. Further, the Hercher patent, like the Allman patent, teaches that the cord providing the electrical house current to the heater is to be installed through the firewall, which is a difficult task.
Two other patents, Eversull U.S. Pat. No. 3,673,379 and Edlund et al. U.S. Pat. No. 3,870,855, show motor vehicle heaters with blowers that use house current to warm the interior of the vehicle prior to starting the vehicle. The Edlund patent teaches a heater mounted in the congested front portion of the vehicle beneath the dash. Both the Edlund and the Eversull patents show heaters that blow directly into the interior of the car, resulting in the interior being warmed before the windows start to defrost.
What is needed is an easily installable car heater that is run by house current to simultaneously pre-warm a vehicle and defrost the windows.